Postnuke

i uploaded all needed files, at least i believe so, i did the install pages an it completed "successfully", but when i try to go to the page i get this "Unable to select database", anyoe know what i might have forgot or missed

i guess when i was uploadin some files were not goin so i had to go through an watch the upload to make sure all files were upping correctly and it worked,yes i edited the config and already had the mysql, it was a file problem,